To Useful Island!
March 6th, 2017
Today we had a disappointing mooring “recovery”. We located the 200m mooring in the Gerlache Strait and sent release signals to the seafloor. The releases confirmed they had released and we waited eagerly to see the floats rise to the surface. Ten minutes passed. Twenty minutes passed. No floats. The mooring has 2 acoustic releases as a fail-safe in case one of the releases failed in some way during deployment; the second release could still allow us to recover the mooring. So, a release signal was sent to the second release. It too responded, confirming release. Again, we waited. No sign of the surface floats. Communication with the releases showed that the mooring wasn’t moving from the seafloor. Was it fouled? Did some of its floatation fail, keeping it at the seafloor rather than bringing it to the surface? There is no way to know since we cannot see the mooring >200m below us. In hopes that the tides would break the mooring free, we waited for several hours while triangulating its exact position and determining whether it was rising from the seafloor.
In the meantime, it was decided that we could quickly multi-task and send zodiacs to nearby Useful Island to remove one of our Automated Weather Stations (AWS). Everyone quickly assembled and geared up for a trip ashore. We all grabbed our waterproof gear for the boat ride, water, snacks, changes of socks, gloves and clothing, a hot drink, and our floatation jackets. We loaded into the zodiac and set out for Useful Island. For those of us who had set up this station a year ago, the site now looked drastically different. There was very little snow and instead, the island was entirely rocky terrain covered with penguins and fur seals. We pulled up to the landing site and the rocky island towered above us. This would be tricky. Perhaps our beloved “Useful Island” wasn’t so Useful!
The weather station atop Useful Island is comprised of 2 solar panels, 12 x 75lb batteries (much like a car battery), a tripod holding an anemometer to measure wind speed and direction, as well as relative humidity, temperature, atmospheric pressure, and irradiance sensors. This station has been sending real-time weather data via satellite every 15 minutes since it was first deployed in December 2015 but it was time for it to come down. The station was disassembled and had to be hand carried down the 250 m rocky island to be loaded into zodiacs and sent back to the ship. We carefully carried the gear down the rocky slope, dodging penguin nests, Skuas flying overhead, and the sunning fur seals at the landing site. After only 3 hours, we had managed to haul all of the gear off of Useful Island. Looking back at the island from the zodiac and reminiscing of the installation trip over one year ago, I realized that perhaps it lived up to its name and been a very useful site after all!